Crankcase emission control valve

[mowerman]

I would really like to do away with said control valve so thought I would remove it and reroute the pipe from the rocker cover straight to the inlet manifold, easy peasy..............

The car ran like s*&T, wouldn`t tick over, was lumpy at low revs and misfired at anything above 2500 rpm?  :-/  Replaced the valve and everything was back to normal  >:( So how can I do away wth the valve but still maintain a sweet running engine? Any of you tuning guru`s know? Advice, as ever greatfully received. Steve.

[Clive]

dump the valve, blank the manifold tapping. Run the rocker breather to a catch tank (ie any bottle type thing, apparently coke bottles are popular with the racers) or just to open air somewhere under the car. I prefer the bottle solution, a £1 sigg type bottle does me.
Clive

[Steve AKA vitessesteve]

If you vet staraight to air you may have problem with using the car on a track.  Use a catch tank - some like a Sig bottle look great if polished to be shiney!

[Nick Moore]

The valve limits the amount of air being sucked into the inlet manifold. If you want to do away with it but not vent to a bottle or the air, fit a limiting valve (I think they're called PCVs). Otherwise, as you found the engine will run lean.

[Deleted User]

you can change it for a modern car pcv valve which is a lot less troublesome. Mine is done like that but always #3 cylinder runs leaner than the others so I think it is letting too much air in. I'd like to redrill it into the pad right by the carb so it vents into the central air stream.

One thing if you use a catch can/bottle then the car always smells of crankcase fumes and will need very good sealing around the gearbox tunnel and  heater intake to keep it out of the cabin. I tried this and found it impossible to stop.